Single neurons within the STN may show bursting activity with intraburst firing rates roughly between 100 and 300 Hz (Wichmann and Soares, 2006, Gale et al., 2009, Sanders et al., 2013, Sharott et al., 2014). Some of the previously reported modulations of bursting activity seem to be in line with those for HFO. Like the spectral amplitude of HFO, the number of bursts increases with movement (Gale et al., 2009). Also, bursting occurs in a slightly more oscillatory fashion in the parkinsonian state (Wichmann and Soares, 2006). However, other findings are more difficult to reconcile. For example, it is known that bursting occurs more frequently in parkinsonian states compared to normal physiological conditions (Lobb, 2014), but we did not find a significant correlation between the spectral amplitude of HFO and UPDRS scores nor did we observe a difference in mean HFO power between ON and OFF medication states (independent t-test: t(97) = 0.702, p = .484). Also, the intraburst frequency is higher in the parkinsonian state (Sanders et al., 2013, Sharott et al., 2014), whereas we observed the opposite pattern
